I'm not an expert by any means, but it looks like your maths are out a little. Surely if you're going fast enough to escape orbit, it doesn't matter how much thrust you've got once you're past that point, as there's nothing to slow you down? So anything above 25k mph would be enough?

This was a great article though. I read it in the print version of FT a while back and the story of the Italian guys tracking the launches, and how they found out the frequencies is fascinating.

Then it's a matter of how quickly you want to get there and how much fuel you have. 18,000mph relative to the earth just puts you in a high or elliptical orbit. I picked 43,000mph in case the article meant 18,000mph on top of escape velocity. 43,000 mph for 48 years puts you at almost 97 Astronomical units, or about twice the distance of Pluto's orbit.

I think there was a Japanese robotic mapping mission that took a few months to get to the moon, using almost no fuel and an assist from the earth's gravity.

Now I'm gonna go look some stuff up.

It was actually three days, not five, to the moon, so make it 25000 + 3500 = 28500mph? I'm leaving out acceleration and braking, etc. The Saturn rocket burned 2-1/2 stages to get to low earth orbit, then used the rest of the fuel in the third stage to send the crew to the moon, and that was in 1968.

Voyager 1 passed the above mark after 30 years (September 2007), thanks to a big rocket and a few planetary gravity assists.

To think, one day if we ever actually get active about getting out there, the legends of the Lost Cosmonaut and his Phantom Capsule haunting the spaceways may put irrational fear into our extra solar explorers. Or at least frighten off meddling kids who try to snoop around abandoned space mines.

@LBA great read ! anyone else get the need to read the # 6 of Planetary ? i always wanted to know what happened to the guys in the CCP ship, sended after the soviets learn about the Four ship... that was my favorite number of Planetary...